JP7184239B2 - Elastic adhesive film and display device including the same - Google Patents

Description

This application claims the benefit of the filing date of Korean Patent Application No. 10-2018-0064864 filed with the Korean Intellectual Property Office on June 5, 2018, the entire contents of which are incorporated herein.
TECHNICAL FIELD The present application relates to a stretchable adhesive film and a display device including the same.

Conventionally, display devices have been developed such as unbreakable displays, curved displays, bent displays, foldable displays, and rollable displays. It is

Currently, the mobile field with a bent display type is at the stage of commercialization, and the mobile field using a foldable display is expected to emerge in earnest. . Also, the speed of development in the field of electrical equipment using pOLED is remarkable.

In particular, recently, a stretchable display has been developed and the demand for it is increasing. In order for a display to exhibit stretchability, it should have a characteristic of elongation in both directions, unlike a conventional display device, which is not simply deformed in one direction.

In order to realize a stretchable display, all the films forming the display must be stretchable. The material must likewise be highly elastic and deformable.

In particular, applications of stretchable displays include touch screen panels, wearable displays in the form of fibers, and medical ( medical), it is supposed to be applicable to the intended display.

On the other hand, the existing adhesives and substrates used as display substrates do not have excellent stretchability and deformability. It has the property that it is difficult to have

Therefore, in consideration of such a situation, it is possible to develop the adhesive force necessary for fixing the base material, and at the same time, the adhesive and the base material layer can be biaxially stretched, and after stretching, the original state It is necessary to develop a pressure-sensitive adhesive film that can be applied to a stretchable display with excellent recovery properties.

The present application seeks to provide a stretchable adhesive film and a display device including the same.

One embodiment of the present application is a stretchable pressure-sensitive adhesive film comprising a base layer containing an elastomer and a first pressure-sensitive adhesive layer provided on one surface of the base layer, wherein the stretchable pressure-sensitive adhesive film has the following formula: To provide an elastic adhesive film that satisfies 1.
[Formula 1]
0.95≤a2/a1≤1
In the above formula 1,
a1 is the stress value at X1 of the elastic adhesive film at 25±2° C. and 50±5% RH (relative humidity),
a2 is the stress value at X1 after elongation/recovery evaluation of the elastic adhesive film 10,000 times at 20% strain at 25±2° C. and 50±5% RH (relative humidity). ,
The X1 is a strain value (%) applied to the elastic adhesive film,
The strain means an elongational strain,
X1 is 20;

In another embodiment, a stretchable pressure-sensitive adhesive film according to one embodiment of the present application, a vapor deposition layer provided on one surface of the stretchable pressure-sensitive adhesive film, and a surface of the vapor deposition layer opposite to the surface in contact with the stretchable pressure-sensitive adhesive film and a base film provided on the elastic adhesive film, wherein the first adhesive layer and the deposition layer of the stretchable adhesive film are in contact with each other.

Finally, it is intended to provide a wearable display device including a stretchable adhesive film according to one embodiment of the present application.

The elastic adhesive film according to one embodiment of the present application has excellent adhesion to a substrate, and in particular, the elastic adhesive film satisfies the above formula 1 and has excellent fatigue durability. shows a physical property that can be restored to the original state even if a strain of 20% level is applied.

The stretchable pressure-sensitive adhesive film according to one embodiment of the present application has the above characteristics, and when used in a stretchable display device later, has excellent recovery ability to the original state and excellent durability, The role of supporting the film forming the display is particularly excellent.

1 is a diagram showing a laminated structure of a stretchable pressure-sensitive adhesive film according to one embodiment of the present application; FIG. 1 is a diagram showing a laminated structure of a stretchable pressure-sensitive adhesive film according to one embodiment of the present application; FIG.

The present specification will be described in more detail below.

In this specification, when a part "includes" a component, it means that it can further include other components, rather than excluding other components, unless specifically stated to the contrary. do.

DETAILED DESCRIPTION OF THE INVENTION Embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the present invention. This invention may, however, be embodied in many different forms and is not limited to the illustrative embodiments set forth herein.

One embodiment of the present application is a stretchable pressure-sensitive adhesive film comprising a base layer containing an elastomer and a first pressure-sensitive adhesive layer provided on one surface of the base layer, wherein the stretchable pressure-sensitive adhesive film has the following formula: To provide an elastic adhesive film that satisfies 1.

[Formula 1]
0.95≤a2/a1≤1
In the above formula 1,
a1 is the stress value at X1 of the elastic adhesive film at 25 ± 2 ° C. and 50 ± 5% RH (relative humidity),
a2 is the stress value at X1 after elongation/recovery evaluation of the elastic adhesive film at 20% strain 10,000 times at 25±2° C. and 50±5% RH (relative humidity);
The X1 is a strain value (%) applied to the elastic adhesive film,
The strain means an elongational strain,
X1 is 20;

The stretchable pressure-sensitive adhesive film according to one embodiment of the present application has excellent adhesion to the substrate, and in particular, the stretchable pressure-sensitive adhesive film satisfies the above formula 1, and has excellent fatigue durability. It exhibits physical properties that allow it to recover to its original state even after strain of % level is applied.

When the value of a2/a1 satisfies the range of formula 1, the stretchable pressure-sensitive adhesive film can maintain the same state as the initial state even after repeating the elongation/recovery evaluation 10,000 times. It has the property of maintaining constant fatigue durability.

The stress value (a1 or a2) at the specific strain (X1) of the elastic adhesive film is a value that varies depending on the content/type of substances contained in the first adhesive layer and the base layer that constitute the elastic adhesive film. and means the value measured at 25° C. with a tensile test measuring device. As the tensile test measuring device, a tensile compression tester (UTM), a texture analyzer, or the like is used, and the device is not limited thereto as long as it can perform a tensile test.

In one embodiment of the present application, the a1 value is set at 25±2° C. and 50±5% RH (relative humidity) by stretching the stretchable adhesive film at both ends in the longitudinal direction so as to have a width of 25 mm and a length of 165 mm. After fixing, it was stretched to X1 at a speed of 100 mm/min using a texture analyzer, and then recovered to the initial state at a speed of 100 mm/min in the opposite direction. At this time, the stress value reaching X1 is defined as a1.

In one embodiment of the present application, the a2 value is set at 25±2° C. and 50±5% RH (relative humidity), with both ends of the stretchable adhesive film having a width of 25 mm and a length of 165 mm. After fixation, 10,000 cycles of elongation and recovery are applied longitudinally to 20% strain at a rate of 1 once per second. After that, using a texture analyzer, it is stretched to X1 at a speed of 100 mm/min, and then recovered to the initial state at a speed of 100 mm/min in the opposite direction. At this time, the stress value reaching X1 is defined as a2.

In the present application, said strain includes an elongational strain, which means that an object elongates and deforms when a force is applied to it. That is, the 20% strain means that an elongational strain is added, and that the object is deformed by 20% compared to before the force is applied to the object. That is, the elongational strain is defined by Equation 2 below, where L0 is the initial length and L is the length of the elongation.
[Formula 2]
(L-L0)/L0×100

In one embodiment of the present application, a1 is the stress value at X1 of the elastic adhesive film at 25±2° C. and 50±5% RH (relative humidity), specifically 0.1 MPa≦ It can satisfy the range of a1≦10 MPa, preferably 0.1 MPa≦a1≦8 MPa, more preferably 0.1 MPa≦a1≦5 MPa.

In one embodiment of the present application, the a2 is X1 after elongation/recovery evaluation of the elastic adhesive film at 20% strain for 10,000 times at 25±2° C. and 50±5% RH (relative humidity). Specifically, it satisfies the range of 0.1 MPa ≤ a2 ≤ 9 MPa, preferably 0.1 MPa ≤ a2 ≤ 7 MPa, more preferably 0.1 MPa ≤ a2 ≤ 4 MPa.

In one embodiment of the present application, the X1 is a strain value (%) applied to the stretchable adhesive film and satisfies 20.

In one embodiment of the present application, when X1 satisfies the range of formula 1, the restoring force is particularly excellent, and when applied to a display device, it has excellent characteristics of long life and durability. When X1 is out of the above range of Formula 1, the restoring force is not good, and durability is deteriorated when applied to a stretchable display device later.

In one embodiment of the present application, the elastomer means a macromolecule that has the property of being stretched when an external force is applied and pulled, and returning to its original length when the external force is removed.

In one embodiment of the present application, the elastomer is silicone rubber, styrene butadiene rubber (SBR), butadiene rubber (BR), nitrile rubber, and ethylene propylene diene monomer rubber (EPDM , Ethylene propylene, diene monimer rubber).

In one embodiment of the present application, the silicone rubber is Methyl silicone (MQ), Vinyl-methyl-silicone (VMQ), Phenyl-vinyl-methyl-silicone (PVMQ). , and fluoro-vinyl-methyl-silicone (FVMQ, Fluoro-vinyl-methyl-silicone).

In another embodiment, the silicone rubber may comprise Methyl silicone (MQ) or Vinyl-methyl-silicone (VMQ).

Since the base material layer contains the elastomer, it has excellent resilience when the external force is removed after applying the external force, and has excellent durability so that it does not break even when 100% or more of the external force is applied. .

In one embodiment of the present application, the base layer containing the elastomer may further contain a silane coupling agent.

When the base material layer according to the present application further contains the silane coupling agent, it has a feature that the adhesiveness to the first adhesive layer increases.

In one embodiment of the present application, the silane coupling agent may be vinylsilane, epoxysilane, or methacrylsilane, and may be used in an amount of 0.01-3 parts by weight based on 100 parts by weight of the elastomer. . Examples of such silane coupling agent compounds include vinyltrimethoxysilane, vinyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, or γ-methacryloxypropyltrimethoxysilane, either alone or You may mix and use it.

In one embodiment of the present application, the stretchable pressure-sensitive adhesive film is provided, wherein the base layer has a thickness of 60 μm or more and 150 μm or less.

In another embodiment, the thickness of the base layer may be 60 μm or more and 150 μm or less, preferably 65 μm or more and 150 μm or less, more preferably 70 μm or more and 150 μm or less.

When the thickness of the base material layer satisfies the above range, it has excellent durability properties even after 10,000 times elongation / recovery evaluation is progressed, and the first adhesive layer and / or the second adhesive layer It has excellent adhesive strength.
The thickness of the base layer means the thickness in the direction in which the base layer and the first adhesive layer are laminated.

In one embodiment of the present application, there is provided a stretchable adhesive film comprising a second adhesive layer on the opposite side of the substrate layer to the side in contact with the first adhesive layer.
In one embodiment of the present application, the first adhesive layer and the second adhesive layer may be the same.
In one embodiment of the present application, the first adhesive layer and the second adhesive layer may be different.
The first adhesive layer will be described below, and the second adhesive layer is the same as the first adhesive layer described below.

In one embodiment of the present application, the first adhesive layer includes one or more adhesives selected from the group consisting of acrylic adhesives, silicone adhesives, urethane adhesives, and rubber adhesives. To provide an adhesive film.

In one embodiment of the present application, the first adhesive layer may contain a polymer containing one or more selected from the group consisting of an acrylate-based resin; and polysiloxane.

A polymer obtained by polymerizing two or more different types of units is called a polymer, and the polymer may have two or more types of units arranged irregularly or regularly.

The polymer may be a random polymer in which monomers are mixed without regularity, a block polymer in which blocks arranged at regular intervals are repeated, or a monomer. may be an alternating copolymer having a form in which is alternately polymerized, or an acrylate-based resin according to one embodiment of the present application; and 1 selected from the group consisting of polysiloxane Polymers comprising the above may be random polymers, block polymers, or alternating polymers.

In one embodiment of the present application, the acrylate-based resin may include a (meth)acrylate-based resin having a weight average molecular weight of 100,000 g/mol to 5,000,000 g/mol.

The weight average molecular weight is one of the average molecular weights in which the molecular weight is not uniform and the molecular weight of a certain polymer is used as a reference, and the molecular weight of the component molecular species of the polymer compound having a molecular weight distribution is expressed as a weight fraction. It is a value obtained by averaging.

The weight average molecular weight is measured by Gel Permeation Chromatography (GPC) analysis.

As used herein, (meth)acrylate is meant to include both acrylate and methacrylate. The (meth)acrylate-based resin may be, for example, a copolymer of a (meth)acrylic acid ester-based monomer and a crosslinkable functional group-containing monomer.

The (meth)acrylic acid ester-based monomer is not particularly limited, but examples thereof include alkyl (meth)acrylates. More specifically, the monomer having an alkyl group having 1 to 12 carbon atoms is pentyl (meth) acrylate, n-butyl (meth) acrylate, ethyl (meth) acrylate, methyl (meth) acrylate, hexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) ) acrylate, dodecyl (meth)acrylate, and decyl (meth)acrylate, or two or more of them.

The crosslinkable functional group-containing monomer is not particularly limited, but may contain, for example, one or more of a hydroxyl group-containing monomer, a carboxyl group-containing monomer, and a nitrogen-containing monomer.

Examples of the hydroxyl group-containing compounds include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (Meth)acrylate, 2-hydroxyethylene glycol (meth)acrylate, 2-hydroxypropylene glycol (meth)acrylate, and the like.

Examples of the carboxyl group-containing compound include (meth)acrylic acid, 2-(meth)acryloyloxyacetic acid, 3-(meth)acryloyloxypropyl acid, 4-(meth)acryloyloxybutyric acid, acrylic acid double, itacon acid, maleic acid, maleic anhydride, and the like.

Examples of the nitrogen-containing monomer include (meth)acrylonitrile, N-vinylpyrrolidone, N-vinylcaprolactam, and the like.

At least one of vinyl acetate, styrene, and acrylonitrile may be additionally copolymerized with the (meth)acrylate resin from the viewpoint of improving other functionality such as compatibility.

In one embodiment of the present application, the acrylate-based resin is selected from the group consisting of alkyl (meth)acrylates, hydroxyalkyl acrylates, and nitrogen-containing monomers.

Examples of the alkyl acrylate and alkyl methacrylate include monomers having an alkyl group having 1 to 12 carbon atoms, such as pentyl (meth)acrylate, n-butyl (meth)acrylate, ethyl (meth)acrylate, methyl (meth)acrylate, Containing one or more of hexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, dodecyl (meth)acrylate, and decyl (meth)acrylate can be done.

The hydroxyalkyl acrylate includes 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 6-hydroxyhexyl acrylate, 8-hydroxyoctyl acrylate, 2-hydroxyethylene glycol acrylate, or 2-hydroxypropylene glycol. acrylates and the like.

Examples of the nitrogen-containing monomer include VP (N-vinyl pyrrolidone).

In one embodiment of the present application, the polysiloxane has a chain of siloxane bonds (--Si--O bonds) and can include polyorganosiloxane.

In one embodiment of the present application, the polysiloxane may be polydimethyl siloxane (PDMS).

In one embodiment of the present application, the first adhesive layer may contain an adhesive composition having a low glass transition temperature (Tg) value, specifically, the glass transition temperature of the adhesive composition is 40° C. or less, preferably may be 45° C. or lower, more preferably 50° C. or lower.

When the pressure-sensitive adhesive composition of the first pressure-sensitive adhesive layer has the glass transition temperature range, the linear viscoelastic range (LVR) is characterized by a wide range, thereby improving the restoring force of the elastic pressure-sensitive adhesive film. characteristics.

In one embodiment of the present application, the stretchable adhesive film is provided, wherein the first adhesive layer has a thickness of 10 μm or more and 100 μm or less.

In another embodiment, the thickness of the first adhesive layer may be 10 μm or more and 100 μm or less, preferably 15 μm or more and 90 μm or less, more preferably 15 μm or more and 80 μm or less.

When the first adhesive layer has the above thickness range, it has particularly excellent adhesion to the base material layer and has particularly excellent recovery power when an external force is applied.

In one embodiment of the present application, the stretchable pressure-sensitive adhesive film has a thickness of 70 μm or more and 250 μm or less.

In another embodiment, the stretchable adhesive film may have a thickness of 70 μm to 250 μm, preferably 80 μm to 200 μm, more preferably 110 μm to 175 μm.

When the thickness of the stretchable pressure-sensitive adhesive film is within the above range, when it is used in a display device later, it has excellent durability and particularly excellent recovery force when an external force is applied.

In one embodiment of the present application, the first adhesive layer is selected from the group consisting of a crosslinkable compound, a dispersant, a silane coupling agent, a photocuring agent, a heat curing agent, a metal salt, and a tackifier. It may additionally include one or more.

According to one embodiment of the present specification, the crosslinkable compound is hexanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate having 2 to 14 ethylene groups. , trimethylolpropane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, 2-trisacryloyloxymethylethyl phthalic acid, the number of propylene groups is 2 to 14 propylene glycol di(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, acidic variants of dipentaerythritol penta(meth)acrylate and dipentaerythritol hexa(meth)acrylate. ) Compounds obtained by esterifying polyhydric alcohols such as mixtures with acrylates (trade names TO-2348 and TO-2349 of Toagosei Co., Ltd. in Japan) with α,β-unsaturated carboxylic acids; trimethylolpropane triglycidyl compounds obtained by adding (meth)acrylic acid to compounds containing glycidyl groups such as ether acrylate adducts and bisphenol A diglycidyl ether acrylate adducts; phthalate diesters of β-hydroxyethyl (meth)acrylate; Ester compounds of compounds having hydroxyl groups or ethylenically unsaturated bonds such as toluene diisocyanate adducts of β-hydroxyethyl (meth)acrylate with polyvalent carboxylic acids, or adducts with polyisocyanates; methyl (meth) acrylate, ethyl (Meth)acrylic acid alkyl esters such as (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate; and 9,9′-bis[4-(2-acryloyloxyethoxy)phenyl]fluorene It can contain one or more selected from the group, and is not limited to these, and common ones known in the art can be used.

According to one embodiment of the present specification, the photocuring agent includes triazine-based compounds, biimidazole compounds, acetophenone-based compounds, O-acyloxime-based compounds, thioxanthone-based compounds, phosphine oxide-based compounds, coumarin-based compounds, and It may be substituted with one or more substituents selected from the group consisting of benzophenone compounds.

Specifically, according to one embodiment of the present specification, the photocuring agent is 2,4-trichloromethyl-(4′-methoxyphenyl)-6-triazine, 2,4-trichloromethyl-(4 '-Methoxystyryl)-6-triazine, 2,4-trichloromethyl-(fipronyl)-6-triazine, 2,4-trichloromethyl-(3',4'-dimethoxyphenyl)-6-triazine, 3-{ 4-[2,4-bis(trichloromethyl)-s-triazin-6-yl]phenylthio}propanoic acid, 2,4-trichloromethyl-(4′-ethylbiphenyl)-6-triazine, or 2,4- Triazine compounds such as trichloromethyl-(4'-methylbiphenyl)-6-triazine;2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenylbiimidazole or 2,2 Biimidazole compounds such as '-bis(2,3-dichlorophenyl)-4,4',5,5'-tetraphenylbiimidazole; 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1 -(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 4-(2-hydroxyethoxy)-phenyl(2-hydroxy)propylketone, 1-hydroxycyclohexylphenylketone, 2,2- dimethoxy-2-phenylacetophenone, 2-methyl-(4-methylthiophenyl)-2-morpholin-1-propan-1-one (Irgacure-907), or 2-benzyl-2-dimethylamino-1-(4- Acetophenone compounds such as morpholinophenyl)-butan-1-one (Irgacure-369); O-acyloxime compounds such as Ciba Geigy's Irgacure OXE 01 and Irgacure OXE 02; 4,4'-bis(dimethylamino ) benzophenone compounds such as benzophenone or 4,4′-bis(diethylamino)benzophenone; thioxanthone compounds such as 2,4-diethylthioxanthone, 2-chlorothioxanthone, isopropylthioxanthone, or diisopropylthioxanthone; 2,4,6-trimethyl such as benzoyldiphenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, or bis(2,6-dichlorobenzoyl)propylphosphine oxide Phosphine oxide compounds; 3,3′-carbonylvinyl-7-(diethylamino)coumarin, 3-(2-benzothiazolyl)-7-(diethylamino)coumarin, 3-benzoyl-7-(diethylamino)coumarin, 3-benzoyl- 7-methoxy-coumarin, or 10,10′-carbonylbis[1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H,11H-Cl]-benzopyrano[6,7 ,8-ij]-quinolidin-11-one and other coumarin-based compounds can be used alone or in combination of two or more, but are not limited thereto.
Also, the thermosetting agent may be one known in the art.

According to one embodiment of the present application, the metal salt may be a Li-containing inorganic salt, and the Li-containing inorganic salt may be LiTFSI (Bis(trifluoromethane) sulfonimide lithium salt).

In one embodiment of the present application, a stretchable film further comprising a release film on at least one surface of the substrate layer opposite to the surface in contact with the first adhesive layer and the opposite surface of the first adhesive layer to the substrate layer in contact. To provide an adhesive film.

The release film is a film for protecting the base layer and the first adhesive layer with a very thin thickness, and is a film excellent in mechanical strength, thermal stability, moisture shielding property, isotropy, etc. can be used. For example, polyethylene terephthalate (PET), acetates such as triacetyl cellulose (TAC), polyesters, polyethersulfones, polycarbonates, polyamides, polyimides, polyolefins, cycloolefins, polyurethanes, and acrylics A resin film or the like can be used, but it is not limited to this as long as it is a commercially available silicone-treated release film.

In the case of the release film in contact with the substrate layer according to the present application, a fluorine-based release film can be used, and a silicone release film can also be used as long as the release property of the substrate layer can be ensured.

In the case of the release film in contact with the first adhesive layer according to the present application, the fluorine-based release film is used when the first adhesive layer is a silicone-based adhesive, and the silicone-based or fluorine-based release film is used in other cases. Available.

In the present application, as the release film, a non-processed PET film or an antistatic film can be used as long as the release property is ensured.

In one embodiment of the present application, a stretchable adhesive film according to one embodiment of the present application, a deposited layer provided on one surface of the stretchable adhesive film, and a surface of the deposited layer in contact with the stretchable adhesive film. A display device including a base film provided on the opposite surface, wherein the first adhesive layer of the stretchable adhesive film and the deposition layer are in contact with each other.

In one embodiment of the present application, the base film is made of PET (polyethylene terephthalate), polyester, PC (polycarbonate), PI (polyimide), PEN (polyethylene naphthalate), PEEK (polyether ether ketone), PAR ( polyarylate), PCO (polycycloolefin), polynorbornene, PES (polyethersulphone), and COP (cycloolefin polymer).

In another embodiment, the base film may be PET (polyethylene terephthalate) or COP (cycloolefin polymer).

In one embodiment of the present application, the thickness of the base film may be 10 μm or more and 100 μm or less, preferably 15 μm or more and 90 μm or less, more preferably 20 μm or more and 75 μm or less.

Moreover, it is preferable that the base film is transparent. The meaning that the base film is transparent here means that the light transmittance of visible light (400 to 700 nm) is 80% or more.
In one embodiment of the present application, the vapor deposition layer may be an organic vapor deposition layer or an inorganic vapor deposition layer.

In one embodiment of the present application, the deposited layer can comprise a variety of inorganic barrier materials such as silicon (Si), aluminum (Al), indium (In), tin (Sn) , at least one metal selected from the group consisting of zinc (Zn), titanium (Ti), copper (Cu), cerium (Ce), and tantalum (Ta), oxides and nitrides of said metals, Metal compounds such as carbides, oxynitrides, or oxycarbides are included.

More specific examples of the metal compound include silicon oxide, aluminum oxide, titanium oxide, indium oxide, tin oxide, indium tin oxide (ITO), tantalum oxide, zirconium oxide, niobium oxide, aluminum silicate (SiAlOx), carbide Boron, tungsten carbide, silicon carbide, oxygen-containing silicon carbide, aluminum nitride, silicon nitride, boron nitride, aluminum oxynitride, silicon oxynitride, boron oxynitride, zirconium oxide boride, titanium boride oxide, composites thereof, etc. metal oxides, metal nitrides, metal carbides, metal oxynitrides, metal oxide borides, diamond-like carbon (DLC), and combinations thereof.

Also, the deposition layer may include an organic layer containing an organic polymer. That is, the deposition layer may be a laminate of an inorganic layer containing the inorganic barrier material and an organic layer.

In one embodiment of the present application, the display device means an organic light-emitting device or an organic electrical device, and is not limited thereto as long as the display device has elasticity.

In one embodiment of the present application, a wearable display device including the stretchable adhesive film is provided.

The wearable display device means a display device that can be worn on the body, and specifically, it can be used as a medical band.

Hereinafter, the embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. This invention may, however, be embodied in many different forms and is not limited to the illustrative embodiments set forth herein.

<Manufacturing example>
The components, weight ratios and thicknesses of the base layer and the first adhesive layer of the stretchable adhesive films used in Examples and Comparative Examples of the present application are shown in Table 1 below.

In Table 1, the LSR (liquid silicone rubber) is a material of Xiameter 9050 30P manufactured by Dow Corning, and is a two-pack type with a main agent A (Part A) and a curing agent B (Part B). It means that it was mixed at a ratio of 20:1, 10:1 and 5:1, and TPU is a product of LG Chem and means a polyurethane-based material.

1. Production of elastic adhesive film (Example 1)
As the base material layer, the ingredients and weight ratios shown in Example 1 in Table 1 were mixed, and stirring and defoaming were carried out. Thereafter, the mixed solution was coated on the fluorine release surface of TS502 (fluorine release film) manufactured by TACS, and dried in an oven at 150° C. for 5 minutes. It was made to have a thickness of

Thereafter, as the first adhesive layer, after adding a curing agent to the acrylic resin polymerized with the components and weight ratios described in Example 1 of Table 1, methyl ethyl ketone (Methyl Ethyl Ketone) was added so that the solid content was 20%. ethyl ketone, MEK) was added to proceed with stirring and defoaming. After that, the mixed solution was coated on the silicone release surface of SKC Haas RF02N (silicone release film), dried in an oven at 120° C. for 3 minutes, and the final thickness was described in Example 1 in Table 1 above. It was made to have a thickness of Thereafter, the base layer and the first adhesive layer were laminated to prepare an elastic adhesive film.

2. Production of stretchable adhesive film (Examples 2-6)
In the production of the stretchable adhesive film of Example 1, the ingredients, weight ratios, and final thicknesses described in Examples 2 to 6 in Table 1 were used as the base layer, and the first adhesive layer was A stretchable adhesive film was produced in the same manner as in the manufacture of the stretchable adhesive film of Example 1, except that the components, weight ratios, and final thicknesses described in Examples 2 to 6 were used.

3. Production of stretchable adhesive film (stretchable adhesive film of Examples 7-9)
As the base material layer, the ingredients and weight ratios shown in Examples 7 to 9 in Table 1 were mixed, and stirring and defoaming were carried out. Thereafter, the mixed solution was coated on the fluorine release surface of TACS TS502 (fluorine release film), dried in an oven at 150 ° C. for 5 minutes, and the final thickness was Example 7 to 9 in Table 1. It was made to have the thickness described in .

After that, 100 parts by weight of Shin-Etsu KR-3700 resin was mixed with 0.5 parts by weight of CAT-PL 50T, which is a platinum catalyst, and dispersed in toluene so that the solid content was 20%. Coated on mold film. Then, it was dried in an oven at 140° C. for 3 minutes, and the final thickness was adjusted to the thickness described in Examples 7-9 in Table 1 above. Thereafter, the base layer and the first adhesive layer were laminated to prepare an elastic adhesive film.

4. Production of stretchable adhesive films (stretchable adhesive films of Comparative Examples 1 and 2)
In the production of the stretchable adhesive film of Example 1, the components, weight ratios, and final thicknesses described in Comparative Examples 1 and 2 in Table 1 were used as the base layer, and the first adhesive layer was A stretchable pressure-sensitive adhesive film was produced in the same manner as the stretchable pressure-sensitive adhesive film of Example 1 except that the components, weight ratios, and final thicknesses described in Comparative Examples 1 and 2 were used.

5. Production of stretchable adhesive film (stretchable adhesive film of Comparative Example 3)
As a base layer, Part A and Part B of the Xiameter 9050 30P product described in Comparative Example 3 of Table 1 were mixed at a weight ratio of 10:1, and stirred and defoamed. Thereafter, the mixture was coated on a PET film and dried in an oven at 150° C. for 5 minutes to prepare a two-layer structure having a final thickness shown in Comparative Example 3 of Table 1 above.

After that, as the first adhesive layer, after adding a curing agent to the acrylic resin polymerized with the components and weight ratios described in Comparative Example 3 in Table 1, methyl ethyl ketone (Methyl Ethyl Ketone) was added so that the solid content was 20%. ethyl ketone, MEK) was added to proceed with stirring and defoaming. Thereafter, the mixed solution was coated on the silicone release surface of SKC Haas RF02N (silicone release film) and dried in an oven at 120° C. for 3 minutes. It was made to have a thickness of Thereafter, the base layer having a two-layer structure and the first adhesive layer were laminated to prepare an elastic adhesive film.

Table 2 below shows the values obtained by evaluating the stretchability and recovery of the stretchable adhesive film of Table 1 under the conditions of Table 2 below.

1. a1: Under 25 ± 2 ° C. and 50 ± 5% RH (relative humidity), the elastic adhesive films of Examples 1 to 9 and Comparative Examples 1 to 3 are stretched in the longitudinal direction so that the width is 25 mm and the length is 165 mm. After fixing the ends, a single stretch and recovery is applied in the longitudinal direction to 20% strain at a rate of once per second. After that, it is stretched to 20% strain at a speed of 100 mm/min, and then recovered to the initial state at a speed of 100 mm/min in the opposite direction. At this time, the stress value at which the strain reached 20% was measured as a1.

2. a2: Under 25 ± 2 ° C. and 50 ± 5% RH (relative humidity), stretch the elastic adhesive films of Examples 1 to 9 and Comparative Examples 1 to 3 in the longitudinal direction so that the width is 25 mm and the length is 165 mm. After fixing the ends, 10,000 cycles of stretching and recovery are applied to 20% strain in the longitudinal direction at a rate of once per second. Thereafter, after stretching to 20% strain at a rate of 100 mm/min, it is recovered to the initial state at a rate of 100 mm/min in the opposite direction. At this time, the stress value at which the strain reached 20% was measured as a2.
A texture analyzer was used as a measuring device for the above a1 and a2.

As can be seen from Examples 1 to 9 in Table 2, in the case of the stretchable adhesive film of the present application, the value of a2/a1*100 is 95 or more, which is excellent in resilience due to elongation. It can be seen that it exhibits excellent characteristics, and that it has a characteristic of extremely excellent durability.

In the case of Comparative Example 1 in Table 2, when the thickness of the base layer is 50 μm, the value of a2/a1*100 is 92.7. From this, it was possible to confirm that the durability was not good.

In the case of Comparative Example 2 in Table 2, TPU (polycaprolactone-based) was used as the base layer, which is a polyurethane-based material, and when used as the base layer of the elastic adhesive film, it has a resilience due to elongation. was confirmed to decrease.

In the case of Comparative Example 3 in Table 2, a PET layer was additionally deposited as a base layer to form a two-layered base layer with an elastic adhesive film, and the values of a1 and a2 in Table 2 (N/ As can be seen from A), when the strain is pulled by 20%, the elastic adhesive film breaks, making it impossible to measure, and thus a2/a1 cannot be measured (N/A) I was able to confirm. In order to apply the stretchable adhesive film to a stretchable display device and a wearable display device, it should have a characteristic of returning to its original state even when a certain level of strain is applied. In the case of Example 3, it could be confirmed that it is not suitable for use in the display device.

That is, when the stretchable adhesive films of Examples 1 to 9 in Table 2 are used in the display device, the durability is excellent compared to the case of applying the stretchable adhesive films of Comparative Examples 1 to 3 to the display device. In addition, it can be confirmed that it is suitable for use in stretchable display devices and wearable display devices because it has excellent recovery ability by stretching.

101: First Adhesive Layer 102: Base Layer 103: Elastic Adhesive Film 104: Second Adhesive Layer

Claims (14)

a substrate layer comprising an elastomer;
A stretchable adhesive film comprising a first adhesive layer provided on one surface of the base material layer,
Said elastomers are methylsilicone (MQ, Methyl silicone), vinylmethylsilicone (VMQ, Vinyl-methyl-silicone), phenylvinylmethylsilicone (PVMQ, Phenyl-vinyl-methyl-silicone), and fluorovinylmethylsilicone (FVMQ, Fluoro-vinyl-methyl-silicone) containing one or more selected from the group consisting of
The elastic adhesive film satisfies the following formula 1:
[Formula 1]
0.95≤a2/a1≤1
In the above formula 1,
a1 is the stress value at X1 of the elastic adhesive film at 25±2° C. and 50±5% RH (relative humidity),
a2 is the stress value at X1 after elongation/recovery evaluation of the elastic adhesive film 10,000 times at 20% strain at 25±2° C. and 50±5% RH (relative humidity). ,
The X1 is a strain value (%) applied to the elastic adhesive film,
The strain means an elongational strain,
X1 is 20; an elastic adhesive film;
a vapor deposition layer provided on one surface of the stretchable adhesive film;
a base film provided on the opposite surface of the vapor deposition layer to the surface in contact with the stretchable adhesive film,
A display device in which the first adhesive layer of the elastic adhesive film and the vapor deposition layer are in contact with each other,
The elastic adhesive film is
a substrate layer comprising an elastomer;
A stretchable adhesive film comprising a first adhesive layer provided on one surface of the base material layer,
The display device, wherein the elastic adhesive film satisfies the following formula 1:
[Formula 1]
0.95≤a2/a1≤1
In the above formula 1,
a1 is the stress value at X1 of the elastic adhesive film at 25±2° C. and 50±5% RH (relative humidity),
a2 is the stress value at X1 after elongation/recovery evaluation of the elastic adhesive film 10,000 times at 20% strain at 25±2° C. and 50±5% RH (relative humidity). ,
The X1 is a strain value (%) applied to the elastic adhesive film,
The strain means an elongational strain,
X1 is 20; A wearable display device comprising a stretchable adhesive film,
The elastic adhesive film is
a substrate layer comprising an elastomer;
A stretchable adhesive film comprising a first adhesive layer provided on one surface of the base material layer,
The wearable display device, wherein the elastic adhesive film satisfies the following formula 1:
[Formula 1]
0.95≤a2/a1≤1
In the above formula 1,
a1 is the stress value at X1 of the elastic adhesive film at 25±2° C. and 50±5% RH (relative humidity),
a2 is the stress value at X1 after elongation/recovery evaluation of the elastic adhesive film 10,000 times at 20% strain at 25±2° C. and 50±5% RH (relative humidity). ,
The X1 is a strain value (%) applied to the elastic adhesive film,
The strain means an elongational strain,
X1 is 20; 2. The stretchable adhesive film according to claim 1 , comprising a second adhesive layer on the opposite side of the substrate layer to the side in contact with the first adhesive layer. The stretchable pressure-sensitive adhesive film according to claim 1 or 4 , wherein the base layer has a thickness of 60 µm or more and 150 µm or less. The stretchable adhesive film according to any one of claims 1 , 4 and 5 , wherein the first adhesive layer has a thickness of 10 µm or more and 100 µm or less. The elastic adhesive film according to any one of claims 1 , 4, 5 and 6 , wherein the elastic adhesive film has a thickness of 70 µm or more and 250 µm or less. From claims 1 and 4 , wherein the first adhesive layer contains one or more adhesives selected from the group consisting of acrylic adhesives, silicone adhesives, urethane adhesives, and rubber adhesives. 8. The stretchable pressure-sensitive adhesive film according to any one of 7 . The first adhesive layer additionally contains one or more selected from the group consisting of a crosslinkable compound, a dispersant, a silane coupling agent, a photocuring agent, a thermosetting agent, a metal salt, and a tackifier. 9. The stretchable pressure-sensitive adhesive film according to any one of Claims 1 and 4 to 8 . The stretch according to claim 1 , further comprising a release film on at least one surface of the base layer opposite to the surface in contact with the first adhesive layer and the opposite surface of the first adhesive layer in contact with the base layer. adhesive film. The elastic adhesive film according to any one of claims 1 and 4 to 10 ,
a vapor deposition layer provided on one surface of the stretchable adhesive film;
A display device comprising:
A display device in which the first adhesive layer of the stretchable adhesive film and the deposition layer are in contact with each other. an elastic adhesive film;
a vapor deposition layer provided on one surface of the stretchable adhesive film;
A base film provided on the opposite surface of the vapor deposition layer to the surface in contact with the elastic adhesive film
A display device comprising:
The elastic adhesive film is
a substrate layer comprising an elastomer;
a first adhesive layer provided on one surface of the base material layer;
A second adhesive layer on the surface opposite to the surface in contact with the first adhesive layer of the base material layer
including
The elastic adhesive film satisfies the following formula 1,
Display device in which the first adhesive layer of the stretchable adhesive film and the deposition layer are in contact with each other:
[Formula 1]
0.95≤a2/a1≤1
In the above formula 1,
a1 is the stress value at X1 of the elastic adhesive film at 25±2° C. and 50±5% RH (relative humidity),
a2 is the stress value at X1 after elongation/recovery evaluation of the elastic adhesive film 10,000 times at 20% strain at 25±2° C. and 50±5% RH (relative humidity). ,
The X1 is a strain value (%) applied to the elastic adhesive film,
The strain means an elongational strain,
X1 is 20; an elastic adhesive film;
a vapor deposition layer provided on one surface of the stretchable adhesive film;
A base film provided on the opposite surface of the vapor deposition layer to the surface in contact with the elastic adhesive film
A display device comprising:
The elastic adhesive film is
a substrate layer comprising an elastomer;
a first adhesive layer provided on one surface of the base material layer;
A release film on at least one surface of the base layer opposite to the surface in contact with the first adhesive layer and the opposite surface of the first adhesive layer in contact with the base layer
including
The elastic adhesive film satisfies the following formula 1,
Display device in which the first adhesive layer of the stretchable adhesive film and the deposition layer are in contact with each other:
[Formula 1]
0.95≤a2/a1≤1
In the above formula 1,
a1 is the stress value at X1 of the elastic adhesive film at 25±2° C. and 50±5% RH (relative humidity),
a2 is the stress value at X1 after elongation/recovery evaluation of the elastic adhesive film 10,000 times at 20% strain at 25±2° C. and 50±5% RH (relative humidity). ,
The X1 is a strain value (%) applied to the elastic adhesive film,
The strain means an elongational strain,
X1 is 20; A wearable display device comprising the stretchable adhesive film according to any one of claims 1 and 4-10 .

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